KR102021719B1 - Treatment system and method for wastewater containing heavy metal - Google Patents

Abstract

The present invention relates to a selective ion separation system for removing heavy metal in wastewater, a controlling method thereof and a production management system. The selective ion separation system to remove heavy metal in wastewater comprises: an electrodialysis process unit which receives wastewater introduced therein, performs electrodialysis for the introduced wastewater to separate the same into concentrated water containing heavy metal and treated water including cyanide, and discharges the same; an electrolytic extraction process unit which receives the inflow of the concentrated water introduced therein and collects heavy metal through electrolytic extraction; an NF filtration process unit which receives the treated water discharged from the electrodialysis process unit and the treated water discharged from the electrolytic extraction process unit introduced therein and discharges the treated water with heavy metal removed therefrom through an NF film filtration and the concentrated water with heavy metal concentrated therein; and an electrooxidation process unit which receives the treated water of the NF filtration process unit introduced therein, and oxidizes and removes cyan compounds and organics in the treated water of the NF filtration process.

Description

Selective Ion Separation System for Removing Heavy Metals in Wastewater, Control Method thereof, and Production Control System {Treatment system and method for wastewater containing heavy metal}

The present invention relates to a selective ion separation system, a control method thereof, and a production management system for removing heavy metals in wastewater. More specifically, the present invention relates to the treatment of wastewater containing heavy metals, cyan and the like, concentrated and separated heavy metals using an electrodialysis method and sent to the electrolytic extraction process to extract the heavy metals to recover the raw material of the process, electrodialysis process Process water and electrolyzed extraction process are mixed and transported to NF filtration process to treat untreated heavy metals and then to electrooxidation process to process cyanide and remaining organics and traces to produce industrial water, It relates to the method of controlling this and the configuration of the system.

Plating wastewater arises from various processes such as plating electrolyzers, metal surface treatment electrolyzers in addition to electroplating and acid-alkali cleaning processes. Plating wastewater contains high and low pH, copper, nickel, chromium, zinc, nitrogen and toxic cyanide, as well as organics, organic reducing agents and nitrogen.

Therefore, heavy metals are present in high concentrations and, if not properly treated, can seriously damage the ecosystem but are difficult to handle. Plating wastewater is generally treated through treatment methods such as lime coagulation, chemical precipitation, alkali-chlorine oxidation, ion exchange and solvent extraction, but additional treatment is required. In addition, heavy metals are discharged as chemical sludge and cannot be recycled as raw materials for the process.

 Wastewater treatment technology based on membrane separation reduces the consumption of raw materials, energy and water, as well as the required sites through the integration of facilities, and can reduce operating costs due to the minimization of wastewater, chemicals and solid waste and automated operation. In addition, heavy metals can be concentrated at high concentrations, and in conjunction with electrolytic extraction technology, heavy metals can be recovered at minimum cost and recycled as raw materials for industrial processes.

The electrodialysis system is a membrane separation process that moves ions in a solution through an ion exchange membrane under the influence of an electric field, thereby producing concentrated water with maximum concentration of ions and treated water with little ions. In general, ion separation efficiency in electrodialysis is very dependent on the composition ratio of ions according to the inflow characteristics, inherent properties of the ion exchange membrane, electrical properties due to the potential difference, hydraulic properties, physicochemical properties of the metal ions, operating conditions.

Many existing researchers have conducted various studies to selectively separate special ions with the same charge through a membrane from a mixture. However, even though many studies on the modification of the ion exchange membrane and the electrodialysis method for permeation of specific ions through the membrane have been conducted, there are no clear results.

Republic of Korea Patent No. 1598493 Japanese Patent Application Laid-Open No. 2016-77954 Republic of Korea Patent Publication No. 2002-0041504 Republic of Korea Patent No. 311951

Therefore, the present invention has been made to solve the conventional problems as described above, according to an embodiment of the present invention, can be solved using a combination of electrodialysis and electrooxidation, electrolytic extraction, nanofiltration process, the existing process The nanofiltration process was installed after the electrooxidation process, but in this case, the problem of accumulation of heavy metals in the electrooxidation process by combining with hydroxyl groups in the electrooxidation process, and the pH for the electrooxidation process, the nanofiltration process, and the effluent must be adjusted. However, when the electrooxidation process is operated after the nanofiltration process, only the pH of the electrooxidation process and the effluent water need to be adjusted, and thus the chemical cost can be greatly reduced, and in particular, the chemical for controlling the pH of the effluent water can be greatly reduced. Can be.

Existing operating systems monitor the status of the system in real time using a touch panel installed in the control panel using a PLC or an HMI programmed in a computer, and control the pH according to the pH value specified by the operator, or use an inflow Although only the level of outflow was controlled, according to the control method according to the embodiment of the present invention, the processing time and the chemical input amount using the control variables specified by the operator as an integrated operation system in which the production management system is operated in addition to the existing operation system. In addition, by controlling the applied power and the like, the treatment efficiency can be improved and the treatment cost can be reduced, and the objective of reducing the production cost of the plating process can be achieved through economical recovery of raw materials and reuse of water.

On the other hand, the technical problems to be achieved in the present invention are not limited to the technical problems mentioned above, and other technical problems that are not mentioned are clearly to those skilled in the art from the following description. It can be understood.

The first object of the present invention, in the selective ion separation system for removing heavy metals in the wastewater, the wastewater is introduced, the wastewater is electrodialyzed to separate the concentrated water containing heavy metals and treated water containing cyanide An electrodialysis process unit for discharging; The concentrated water is introduced, the electrolytic extraction process unit for recovering heavy metals through electrolytic extraction; An NF filtration process unit for discharging the treated water discharged from the electrodialysis process unit and the treated water discharged from the electrolytic extraction process unit to remove the treated water and the concentrated water concentrated heavy metals through NF membrane filtration; And an electrooxidation process unit for oxidizing and removing cyanide compounds and organic matter present in the treated water of the NF filtration process unit, in which the treated water of the NF filtration process unit is introduced. It can be achieved as a selective ion separation system for removal.

And it may be characterized in that it further comprises a floating material removal process unit is provided at the front end of the electrodialysis process unit to remove the suspended matter.

In addition, the electrodialysis process unit includes a treatment tank, a concentration tank, an electrode solution tank, the concentration of heavy metals in the electrode solution used in the electrodialysis process unit as the operation time is elapsed, so that the concentrated water and The electrolytic extraction process may be characterized in that it is transferred to.

The electrolytic extraction process unit is composed of a plurality of stages connected in series according to the type of heavy metal, in order to recover the concentrated metal containing heavy metal and the heavy metal present in the electrode solution, the pH and applied voltage according to the type of heavy metal to be recovered It may be characterized by recovering the heavy metal through the adjustment of.

In addition, the NF filtration step portion of the electrodialysis step portion of the treated water and the electrolytic extraction step of the treated water flows in, the treated water to remove the cation heavy metals are transferred to the electro-oxidation process portion, concentrated water concentrated heavy metals are electrodialysis It may be characterized in that it is mixed with the wastewater of the inlet of the front end of the government re-introduced into the electrodialysis process.

And the electrooxidation process by oxidizing and removing the cyan compound and organic matter present in the treated water of the NF filtration process unit, hypochlorous acid produced in the electro-oxidation process unit is used to clean the NF filtration membrane of the NF filtration process unit. You can do

In addition, the influent electrical conductivity measurement unit for measuring the electrical conductivity of the wastewater flowing into the electrodialysis process unit, the influent pH measurement unit for measuring the pH of the wastewater, and the treatment tank electrical conductivity measurement unit for measuring the electrical conductivity in the treatment tank And, it may be characterized in that it comprises a concentration bath electrical conductivity measuring unit for measuring the electrical conductivity in the concentration tank, and an electrode solution tank electrical conductivity measuring unit for measuring the electrical conductivity in the electrode solution tank.

And an electrical conductivity change rate based on values measured by an influent electric conductivity measuring unit, the influent pH measuring unit, the treated tank electric conductivity measuring unit, the concentrated tank electric conductivity measuring unit, and the electrode solution tank electric conductivity measuring unit. And calculating an operating voltage of the electrodialysis process unit based on the electrical conductivity change rate.

In addition, the electrolytic extraction step pH measuring unit for measuring the pH in the reaction tank of the electrolytic extraction step, and the electrolytic extraction step portion electrical conductivity measuring unit for measuring the electrical conductivity in the reaction tank of the electrolytic extraction step may be characterized in that it further comprises. .

The electrical conductivity change rate is calculated based on the measured value of the electrical conductivity measurement unit of the electrolytic extraction process, and the operating time in the reaction vessel is determined by using the electrical conductivity change rate.When concentrated water is introduced, the pH is measured by the pH measuring unit of the electrolytic extraction process. It may be characterized by recovering the heavy metal by adjusting to an appropriate pH range and applying electricity.

In addition, the NF filtration process unit pH measuring unit for measuring the pH in the reaction tank of the NF filtration process unit, the NF filtration process unit electrical conductivity measurement unit for measuring the electrical conductivity in the reaction tank of the NF filtration process unit, a pressure gauge for measuring the pressure in the reaction tank It may be characterized in that it further comprises.

The electrical conductivity change rate is calculated based on the measured value of the electrical conductivity measurement unit of the NF filtration process unit, and the operating time in the reaction tank is determined using the electrical conductivity change rate. It may be characterized by adjusting.

The method may further include an electrooxidation process pH measuring unit for measuring pH in the reaction tank of the electrooxidation process unit, and an electroconductivity measurement unit for measuring the electrical conductivity in the reaction tank of the electrooxidation process unit. .

The electrical conductivity change rate is calculated based on the measured value of the electrical conductivity measurement unit of the electrooxidation process, the operating time in the reaction vessel is determined using the electrical conductivity change rate, and the pH is measured by measuring the pH when the treated water flows into the electrooxidation process unit. It may be characterized by removing the cyan and organic substances by adjusting to and applying electricity.

A second object of the present invention, in the control method of the electrodialysis process of the selective ion separation system for removing heavy metals in the waste water according to the above-mentioned first object, the pH of the waste water measured through the influent pH measurement unit is set Measuring pH within a range and adjusting pH so as to be within an appropriate range if not within the proper range; If the rate of change of conductivity in the treatment tank is within the setting range, checking whether the rate of change of conductivity in the concentration bath is within the setting range and checking whether the rate of change of conductivity in the electrode solution tank is within the setting range; If the rate of change of the electrode liquid electrical conductivity of the treatment tank, the concentration tank, and the electrode solution tank is within the setting range, driving the voltage by increasing the applied voltage; And maintaining the applied voltage when the electrical conductivity change rate decreases as time passes and decreases within the set range, or operates by decreasing the voltage, and finally stopping the operation when the operating voltage reaches the initial applied voltage. It can be achieved as a control method of the selective ion separation system for removing heavy metals in the waste water characterized in that.

The third object of the present invention is a control method of the electrolytic extraction process of the selective ion separation system for removing heavy metals in the waste water according to the first object mentioned above, if the rate of change of the electrical conductivity is within the set range, to check the pH First step; A second step of continuing the operation if the value of the pH is within an appropriate range and operating after adjusting the pH if the pH is exceeded; a third step of stopping the operation if the pH is within an appropriate range and moving the treated water to a subsequent electrolytic extraction process; And performing the first to third steps with respect to all of the electrolytic extraction processes. It can be achieved as a control method of the selective ion separation system for removing heavy metals in the wastewater.

The fourth object of the present invention is to control the NF filtration process of the selective ion separation system for removing heavy metals in the wastewater according to the first object mentioned above, and if the rate of change of the electrical conductivity is within the setting range, step; Continuing operation when the value of the pH is within an appropriate range, and operating after adjusting the pH when exceeding the range; And stopping the operation if the pH is within an appropriate range and moving the treated water to a subsequent electrooxidation unit. It can be achieved as a control method of the selective ion separation system for removing heavy metals in the wastewater. .

The fifth object of the present invention is a control method of the electrooxidation process of the selective ion separation system for removing heavy metals in the wastewater according to the first object mentioned above, if the rate of change of the electrical conductivity is within the set range, to check the pH step; Continuing operation when the value of the pH is within an appropriate range, and operating after adjusting the pH when exceeding the range; And stopping the operation if the pH is within an appropriate range and moving the treated water to a treated water tank or a recycling process. The method may be achieved as a control method of a selective ion separation system for removing heavy metals in waste water. have.

According to an embodiment of the present invention, it can be solved by using a combination of electrodialysis and electrooxidation, electrolytic extraction, nanofiltration process, the existing process was installed after the nanofiltration process, but in this case electrooxidation In the process, the heavy metal is combined with hydroxyl group and accumulated in the electrooxidation process, and the pH of the electrooxidation process, the nano filtration process, and the effluent water has to be adjusted, but if the electrooxidation process is operated after the nano filtration process, Since only the pH of the effluent is adjusted, the cost of the drug can be greatly reduced, and in particular, the drug for controlling the pH of the effluent has a significant effect.

Existing operating systems monitor the status of the system in real time using a touch panel installed in the control panel using a PLC or an HMI programmed in a computer, and control the pH according to the pH value specified by the operator, or use an inflow Although only the level of outflow was controlled, according to the control method according to the embodiment of the present invention, the processing time and the chemical input amount using the control variables specified by the operator as an integrated operation system in which the production management system is operated in addition to the existing operation system. By controlling the applied power and the like, the treatment efficiency is improved and the treatment cost is reduced, and the production cost of the plating process can be reduced by economical recovery of raw materials and reuse of water.

On the other hand, the effect obtained in the present invention is not limited to the above-mentioned effects, other effects that are not mentioned will be clearly understood by those skilled in the art from the following description. Could be.

The following drawings, which are attached to this specification, illustrate exemplary embodiments of the present invention, and together with the detailed description thereof, serve to further understand the technical spirit of the present invention, and thus, the present invention is limited only to the matters described in the drawings. It should not be interpreted.
1 is a block diagram of a selective ion separation system according to an embodiment of the present invention,
Figure 2 is a block diagram of a selective ion separation system showing a multi-stage electrolytic extraction process according to an embodiment of the present invention,
Figure 3 is a schematic diagram of the SCADA system and production management system for the control of the selective ion separation system according to an embodiment of the present invention,
Figures 4a, 4b and 4c is a graph of electrical conductivity change in the electrodialysis process,
5a, 5b and 5c is a graph of change in heavy metal concentration in the electrodialysis process,
6a, 6b and 6c is a graph of pH change in the electrodialysis process,
7a, 7b and 7c are graphs of the conductivity change rate according to the operating time in the electrodialysis process,
8 is a flowchart of a control method of an electrodialysis process according to an embodiment of the present invention;
9 is a heavy metal concentration change graph in the electrolytic extraction process according to an embodiment of the present invention,
10 is a flowchart of a control method of an electrolytic extraction process according to an embodiment of the present invention;
11 is a flow chart of a control method of the NF filtration process according to an embodiment of the present invention,
12 is a flowchart of a control method of an electrooxidation process according to an embodiment of the present invention;
13 is a block diagram of a production management system program according to an embodiment of the present invention;
14 is a block diagram of a data normalization method according to an embodiment of the present invention;
15 is a block diagram of a watch dog according to an embodiment of the present invention.

Objects, other objects, features and advantages of the present invention will be readily understood through the following preferred embodiments associated with the accompanying drawings. However, the present invention is not limited to the embodiments described herein and may be embodied in other forms. Rather, the embodiments introduced herein are provided so that the disclosure may be made thorough and complete, and to fully convey the spirit of the invention to those skilled in the art.

In the present specification, when a component is mentioned to be on another component, it means that it may be formed directly on the other component or a third component may be interposed therebetween. In addition, in the drawings, the thickness of the components are exaggerated for the effective description of the technical content.

Embodiments described herein will be described with reference to cross-sectional and / or plan views, which are ideal exemplary views of the present invention. In the drawings, the thicknesses of films and regions are exaggerated for effective explanation of technical content. Therefore, the shape of the exemplary diagram may be modified by manufacturing techniques and / or tolerances. Accordingly, the embodiments of the present invention are not limited to the specific forms shown, but also include changes in forms generated according to manufacturing processes. For example, the region shown at right angles may be rounded or have a predetermined curvature. Thus, the regions illustrated in the figures have properties, and the shape of the regions illustrated in the figures is intended to illustrate a particular form of region of the device and is not intended to limit the scope of the invention. Although terms such as first and second are used to describe various components in various embodiments of the present specification, these components should not be limited by such terms. These terms are only used to distinguish one component from another. The embodiments described and illustrated herein also include complementary embodiments thereof.

The terminology used herein is for the purpose of describing particular embodiments only and is not intended to be limiting of the invention. In this specification, the singular also includes the plural unless specifically stated otherwise in the phrase. As used herein, the words 'comprises' and / or 'comprising' do not exclude the presence or addition of one or more other components.

In describing the specific embodiments below, various specific details are set forth in order to explain the invention more specifically and to help understand. However, those skilled in the art can understand that the present invention can be used without these various specific details. In some cases, it is mentioned in advance that parts of the invention which are commonly known in the description of the invention and which are not highly related to the invention are not described in order to prevent confusion in explaining the invention without cause.

Selective Ion Separation System

Hereinafter, the configuration and function of the selective ion separation system 1 according to the embodiment of the present invention will be described. First, Figure 1 shows a block diagram of a selective ion separation system 1 according to an embodiment of the present invention, Figure 2 is a selective ion separation system 1 showing a multi-stage electrolytic extraction process according to an embodiment of the present invention The configuration diagram is shown.

As shown in Figure 1 and 2, the selective ion separation system 1 according to an embodiment of the present invention is an electrodialysis process unit 10, an electrolytic extraction process unit 20, NF filtration process unit 70, It is configured to include an electrooxidation process unit (80). Waste water containing heavy metal is introduced into the electrodialysis process unit (10). At the front end of the electrodialysis process unit 10, a floating material removing process such as a membrane filtration facility for removing the floating material may be additionally installed.

Wastewater introduced into the electrodialysis process unit 10 is separated into treated water containing cyanide and concentrated water containing heavy metals, and the treated water is transferred to the NF filtration process unit 70 and the concentrated water is electrolytic extraction process unit ( 20). At this time, since the concentration of heavy metals increases as the operation time passes in the electrode solution used in the electrodialysis process unit 10, the electrolytic extraction process unit 20 is transferred together with the concentrated water after a predetermined time. The electrolytic extraction process unit 20 is a device for recovering heavy metals contained in the concentrated water and the electrode solution containing heavy metals to recover the heavy metals by adjusting the pH and the applied voltage, depending on the type of heavy metals to be recovered. The process unit 20 is each operated in a series of processes.

The heavy metal attached to the surface of the reduction electrode plate (cathode) of the electrolytic extraction step 20 may be recovered at regular intervals and used as a raw material of the plating process, or the reduction electrode plate may be used directly as a raw material of the electroplating process. The treated water discharged from the final electrolytic extraction step 20 is transferred to the NF filtration step 70.

In the NF filtration process unit 70, the treated water of the electrodialysis process unit 10 and the treated water of the electrolytic extraction process unit 20 are mixed and processed. In the NF filtration process unit 70, the treated water from which the heavy metal is removed and the concentrated water concentrated of the heavy metal are produced. The treated water of the NF filtration process unit 70 is transferred to the electro-oxidation process unit 80 and the concentrated water is mixed with the wastewater of the inlet unit and flowed back into the electrodialysis process unit 10.

In the electrooxidation process unit 80, the cyan compound, organic matter, and the like present in the treated water of the NF filtration process unit 70 are oxidized and removed. At this time, the hypochlorous acid produced by the electrooxidation process unit 80 can effectively control the fouling of the membrane when used to clean the NF filtration membrane, as well as improve the stability of processing performance, increase the cleaning cycle, and reduce the cleaning cost. have.

3 shows a schematic diagram of a SCADA system and a production management system for controlling the selective ion separation system 1 according to an embodiment of the present invention. Control of the selective ion separation system (1) according to an embodiment of the present invention uses a SCADA system using a PLC and a production management system that automatically controls the processing time, chemical input, applied power, etc. using control parameters specified by the operator To control.

The PLC-based SCADA system provides real-time operation of the instrument according to the current control set-point and the value of the instrument installed in the field, and the production management system monitors the value of the instrument in real time and analyzes the value of the instrument to set the range. The new set-point is automatically transferred to the SCADA system when it is reached, so that the whole process can be operated through the new control set-point, which minimizes the difference according to the operator's skill level and operates 24 hours for unattended operation and chemical cost. It contributes to the economic recovery of heavy metals by reducing, reducing the reaction time and reducing the recovery cost of heavy metals.

<Control method>

4A, 4B and 4C show graphs of change in conductivity in the electrodialysis process. 5A, 5B, and 5C show graphs of changes in heavy metal concentrations in the electrodialysis process.

Referring to Figure 4 showing the electrical conductivity change in the electrodialysis process unit 10, the electrical conductivity in the dilution tank (treated water) (Fig. 4a) is a heavy metal ions are moved to the concentration tank as the operation time elapses, the electrical conductivity is reduced. On the other hand, the concentration tank (Fig. 4b) is the electrical conductivity is increased as the heavy metal ions in the dilution tank is moved. In addition, the electrical conductivity in the electrode solution tank (Fig. 4c) is increased by the concentration diffusion of heavy metal ions in the concentration tank and dilution tank. The movement of these ions can be confirmed through FIGS. 5A, 5B and 5C.

6A, 6B, and 6C show graphs of pH change in the electrodialysis process unit 10. As shown in Figure 6a to Figure 6c, looking at the pH change in the electrodialysis process unit 10, the pH in the dilution tank (treated water) is increased as the operation time elapses. This is because when all ions on the surface of the ion exchange membrane move inside the ion exchange membrane, ionic materials on the surface of the ion exchange membrane are instantaneously present in the polarization of water.

Hydrogen ions (H ⁺ ) are monovalent ions, and because of their small size, are rapidly moved into the cation exchange membrane and then to the concentration tank. This reduces the pH of the concentration bath and increases the pH of the dilution bath. In addition, even in the case of the electrode liquid bath, the pH is reduced due to the diffusion by the difference in pH over time. After a certain time, the pH of the dilution tank tends to increase slightly, the pH of the concentrate tank also increases slightly, and the concentration tank tends to decrease slightly.

This is caused by more polarization of water as the concentration of ions to be transferred is lowered, but it is due to the change of quantity in each tank due to charge balance, diffusion by concentration difference, and electroosmosis. However, these changes may vary depending on the experimental conditions.

Therefore, in order to operate the electrodialysis process unit 10 stably, it is necessary to install and operate various water quality measuring instruments including measuring instruments for measuring heavy metals in influent and treated water, concentrated water, and electrode solution tanks. There is a lot of trouble. Therefore, in order to operate in a more economical manner, it is preferable to control by using the electrical conductivity in each reaction tank.

In general, the method of controlling conductivity is applied by setting the lower limit of the conductivity and stopping the operation when the lower limit is reached, but this shows a big difference in operating time according to the concentration in the influent, increasing the operating cost and measuring the conductivity meter. In case of failure, the processing performance can be drastically reduced. Therefore, it is reasonable to use the rate of change over time by using the electrical conductivity in each reactor as a method for solving this. Equation 1 below shows the change rate of the electrical conductivity.

[Equation 1]

lnC _t = lnC ₀ -kt

Where k is the primary rate constant and C ₀ and C _t represent the influent electrical conductivity at the beginning of the experiment and the electrical conductivity at time t. 7A, 7B and 7C show graphs of change in conductivity according to operation time in an electrodialysis process.

4A, 7B, and 7C are calculated and illustrated in accordance with Equation 1 below. Looking at Figures 7a, 7b, 7c, it can be seen that the inflection point of the electrical conductivity occurs in the treatment bath, the concentration bath, the electrode solution bath. In particular, the electrical conductivity inflection point in the treatment tank means that the moving speed of the heavy metal is reduced. If the operation is the same as before even after the inflection point, the economic efficiency decreases due to the decrease in electrical efficiency. Therefore, after the inflection point, in order to secure economic feasibility, it is necessary to apply various methods such as the end of the operation, the movement to the next electrodialysis process, the increase of the flow rate, and the decrease of the applied voltage.

However, when the operation is terminated, the concentration in the concentrated water is lowered, and the heavy metal recovery amount in the subsequent electrolytic extraction process unit 20 decreases, and the inflow concentration in the NF filtration process unit 70 increases, thereby increasing the operating time, thereby decreasing economic efficiency. Done. In the case of moving to the next electrodialysis process unit 10, as the equipment is added, the initial investment cost and maintenance cost increases, and the power cost of the pump increases even if the flow rate is increased.

Therefore, the most stable and effective method is to lower the operating voltage. However, if the operation voltage is lowered inadvertently, the operation time increases, so it must be properly controlled. Therefore, in order to control effectively, the control logic shown in FIG. 8 must be used. 8 shows a flowchart of a control method of an electrodialysis process according to an embodiment of the present invention.

1 and 2, the selective ion separation system 1 for removing heavy metals in the wastewater according to an embodiment of the present invention, the electrical conductivity of the wastewater flowing into the electrodialysis process unit 10 Influent water conductivity measurement unit 2, an influent pH measurement unit 3 for measuring the pH of the wastewater, a treatment tank electric conductivity measurement unit 12 for measuring the electrical conductivity in the treatment tank 11, and a concentrated tank It can be seen that it includes a concentrated tank electric conductivity measuring unit 14 for measuring the electrical conductivity in (13), and an electrode liquid tank electrical conductivity measuring unit 16 for measuring the electrical conductivity in the electrode liquid tank 15. The influent water conductivity measuring unit 2, the influent pH measuring unit 3, the treatment tank electric conductivity measuring unit 12, the concentrated tank electric conductivity measuring unit 14, and the electrode solution tank electric conductivity measuring unit 16 The electrical conductivity change rate is calculated based on the measured value, and the operating voltage of the electrodialysis process unit 10 is adjusted based on the electrical conductivity change rate.

If wastewater is introduced, the pH should be measured to reduce the heavy metals to an appropriate level so that they do not form hydroxides, or too low pH may damage the ion exchange membranes and increase to an appropriate level. The appropriate level of pH may vary depending on the heavy metals to be removed and the site of installation. When the driver decides the proper voltage at the start of operation, the production management system continuously monitors the conductivity and calculates the rate of change at regular intervals.

If the electrical conductivity change rate of the treated water is within the setting range, check whether the electrical conductivity change rate in the concentrated water is within the setting range, and if it is within the range, check whether the change rate of the electrode liquid is within the setting range. If the rate of change of the electrode solution of each reactor is within the set range, the voltage is increased and operated, which can be determined by the driver and can be specified according to the site conditions. As time elapses, the rate of change decreases, and if the value falls within the set range, the applied voltage is maintained or reduced, and the operation is finally stopped. When the operating voltage finally reaches the first applied voltage, the operation is stopped.

At this time, the stop of driving may be driven differently according to the driver's experience and site conditions. Thereafter, the treated water is transferred to the NF filtration process unit 70, and the concentrate and the electrode solution are transferred to the electrolytic extraction process unit 20 when the water level is set at the target value or the electrical conductivity reaches the target value. In this case, even if a failure occurs in some of the conductivity meters in each reactor, it is possible to operate stably because it can be controlled using other instrument values. If all conductivity meters fail, the unit will operate at the specified operating time. If the concentration of influent is very low, the process may be operated using the lower limit of the conductivity.

9 is a graph showing the concentration change of heavy metals in the electrolytic extraction process according to an embodiment of the present invention. That is, Figure 9 shows a change in the concentration of heavy metals in the electrolytic extraction step 20 to move the concentrated water and the electrode solution. In particular, in the case of wastewater containing copper and nickel, as shown in Figure 9, by changing the pH and applied voltage it is possible to recover each heavy metal separately from the mixed wastewater. However, in the case of recovery in a single reaction tank, it is desirable to move the treated water to the subsequent electrolytic extraction step 20 because it needs to replace the cathode (cathode) to maximize the convenience and recovery of the operation. The subsequent electrolytic extraction unit 20 would be ideally operated with the same number of processes as the type of heavy metal to be recovered.

In order to operate the electrolytic extraction process unit 20 stably, a measuring instrument capable of measuring heavy metals must be installed and operated in the reaction tank, but there is a problem in that the initial investment cost and the maintenance cost are high.

Therefore, in order to operate in a more economical manner, it would be ideal to determine the operating time in each reactor by using the electrical conductivity change rate in the reactor as shown in Equation 1 above. 10 is a flowchart illustrating a control method of an electrolytic extraction process according to an embodiment of the present invention. As shown in FIG. 1, an electrolytic extraction step pH measuring unit 22 for measuring the pH in the reaction tank of the electrolytic extraction step 20, and an electrolysis measuring electric conductivity in the reaction tank of the electrolytic extraction step 20. It can be seen that the extraction process unit includes an electrical conductivity measurement unit 21. Then, the electrical conductivity change rate is calculated based on the measured value of the electrical conductivity measurement unit 21, and the operating time in the reaction tank is determined using the electrical conductivity change rate. 22), the pH is measured, adjusted to an appropriate pH range, and the heavy metal is recovered by applying electricity.

In addition, as shown in Figure 2, the # 1 electrolytic extraction process unit 30, # 2 electrolytic extraction process unit 40, ... for the recovery by type of heavy metal. , when the #n electrolytic extraction step 50 is installed in series, the # 1 electrolytic extraction step pH measuring unit 32 and # 1 electrolysis to measure the pH in the reaction tank of the # 1 electrolytic extraction step 30 # 1 electrolytic extraction process unit for measuring the electrical conductivity in the reaction tank of the extraction process unit 30, the electrical conductivity measuring unit 31, and # 2 electrolyte for measuring the pH in the reaction tank of the # 2 electrolytic extraction process unit 40 Extraction process unit pH measurement unit 42, # 2 electrolytic extraction process unit electrical conductivity measurement unit 41 for measuring the electrical conductivity in the reaction tank of the # 2 electrolytic extraction process unit 40, the #n electrolytic extraction hole #N electrolytic extraction process unit pH measuring unit 52 for measuring the pH in the reaction tank of the government unit 50, #n electrolytic extraction process unit electrical conductivity for measuring the electrical conductivity in the reaction tank of the #n electrolytic extraction process unit 50 It can be seen that the measurement unit 51 is included.

When wastewater flows into the electrolytic extraction process # 1 (30) of FIG. 2, the pH is measured, adjusted to an appropriate pH range, and the heavy metal is recovered by applying electricity. Since the conductivity decreases as the operation time elapses, the change rate is calculated according to Equation 1 at regular intervals.

If the rate of change of electric conductivity is within the setting range, check the pH and continue operation if the value of pH is within the appropriate range, and operate after adjusting the pH if it exceeds the range, but stop the operation if the pH is within the proper range. The treated water is transferred to the subsequent electrolytic extraction process # 2. This series of processes is performed identically in all electrolytic extraction processes, and the operator can set the range of electrical conductivity and pH.

In addition, when the conductivity meter fails, it is controlled by the rate of change of pH, and when both the conductivity meter and the pH meter fail, the operation time is specified. When the operation of the last electrolytic extraction step #n is finished, the treated water is moved to the NF filtration step 70. The operator may recover the heavy metal attached to the cathode of each electrolytic extraction process or use the cathode as a raw material of heavy metal. If the concentration of influent is very low, the process may be operated using the lower limit of the conductivity.

In order to stably operate the NF filtration process unit 70, but must be installed and operated to measure the heavy metal in the reaction tank, there is a problem that takes a lot of initial investment and maintenance costs. Therefore, in order to operate in a more economical manner, it would be ideal to determine the operating time in each reactor by using the electrical conductivity change rate in the reactor as shown in Equation 1 above. 11 is a flowchart illustrating a control method of an NF filtration process according to an embodiment of the present invention. 1 and 2, the treated water conductivity measuring unit 61 for measuring the electrical conductivity of the treated water flowing into the NF filtration process unit 70, the treated water pH measuring unit for measuring the pH ( NF filtration process unit pH measurement unit 72 for measuring the pH in the reaction tank of the NF filtration process unit 70, and NF filtration hole for measuring the electrical conductivity in the reaction tank of the NF filtration process unit 70; It can be seen that it comprises a government electrical conductivity measurement unit 71, and a pressure gauge 73 for measuring the pressure in the reaction tank. Then, the electrical conductivity change rate is calculated based on the measured value of the electrical conductivity measurement unit 71 of the NF filtration process unit, and the operating time in the reaction tank is determined using the electrical conductivity change rate, and through the pH measurement unit 72 of the NF filtration process unit. The pH is measured and adjusted to the appropriate pH range.

When wastewater flows into the NF filtration process unit 70, the pH is measured and adjusted to an appropriate pH range. Since the conductivity decreases as the operation time elapses, the change rate is calculated according to Equation 1 at regular intervals. If the rate of change of electric conductivity is within the setting range, check the pH and continue operation if the value of pH is within the appropriate range, and operate after adjusting the pH if it exceeds the range, but stop the operation if the pH is within the proper range. The treated water is transferred to a subsequent electrooxidation process.

If the conductivity meter fails, it is controlled by the rate of change of pH. If both the conductivity meter and the pH meter fail, the operation time is specified. If the concentration of influent is very low, the process may be operated using the lower limit of the conductivity.

In order to operate the electro-oxidation process unit 80 stably, a measuring instrument capable of measuring cyanide (CN) and organic substances, etc. must be installed and operated in the reaction tank, but there is a problem in that initial investment and maintenance costs are required. Therefore, in order to operate in a more economical manner, it would be ideal to determine the operating time in each reactor by using the electrical conductivity change rate in the reactor as shown in Equation 1 above. 12 is a flowchart illustrating a control method of an electrooxidation process according to an exemplary embodiment of the present invention. In addition, as shown in Figures 1 and 2, the electrochemical oxidation step pH measuring unit 82 for measuring the pH in the reaction tank of the electro-oxidation process unit 80, and the electricity in the reaction tank of the electro-oxidation process unit 80 It can be seen that the electrochemical process unit for measuring the conductivity is configured to include an electrical conductivity measuring unit 81. Then, the electrical conductivity change rate is calculated based on the measured value of the electrical conductivity measuring unit 81, the electrical conductivity change rate is used to determine the operating time in the reactor, and the treated water flows into the electrooxidation process unit 80. When the pH is measured to adjust to the appropriate pH range and applying electricity to remove the cyan and organic matter.

When the wastewater flows into the electrooxidation process unit 80, the pH is measured, adjusted to an appropriate pH range, and electricity is removed to remove cyanide and organic substances. Since the conductivity decreases as the operation time elapses, the change rate is calculated according to Equation 1 at regular intervals. If the rate of change of electric conductivity is within the setting range, check the pH and continue operation if the value of pH is within the appropriate range, and operate after adjusting the pH if it exceeds the range, but stop the operation if the pH is within the proper range. Transfer the treated water to the treatment tank or process. If the conductivity meter fails, it will be operated for the designated operating time. If the concentration of influent is very low, the process may be operated using the lower limit of the conductivity.

<Production Management System>

Existing facilities are operated under different conditions depending on the operator's experience without an integrated operator, and thus the processing cost is continuously increasing. It is necessary to introduce a production management system to overcome these problems, improve efficiency in the installation and operation management of facilities, and achieve cost reduction effects. When the production management system is introduced, users can monitor or control the process of the facility anytime, anywhere, and can manage multiple sites by integrating them.In addition, the work efficiency can be increased through facility history management and groupware, and local, Overcoming time limits can speed up work and increase productivity. By introducing the production management system, the following effects can be expected.

 -Integrated monitoring and control of the unit treatment plant in the integration center

 -Reasonable manpower operation such as unmanned whole plant or night unmanned

 -Secure processing performance through unification and specialization of management system

 -Increase work efficiency and productivity through collaboration and information sharing between operators

 -Maintenance cost reduction and facility life extension by efficient maintenance and facility management

 -Convenient operation that overcomes time and space constraints

Production management system according to an embodiment of the present invention can be largely divided into an online measuring unit, a monitoring unit, a control unit. The online measuring unit is a part that measures the state in each reactor in real time and is composed of various flow meters, temperature, pH, conductivity pressure, and water level meter. Data measured by the on-line water quality meter is transmitted to the monitoring unit in real time to provide the status information of the reactor to the operator. The operator controls the reactor by setting the operating factor value through the control unit using the state information and historical information provided in real time. The introduction of this production management system is expected to improve the efficiency of treatment, reduce maintenance costs, and increase fertilizer productivity, while operating facilities are automatically operated.

The production management system establishes the data transmission system for the monitoring, control, and measurement signals of the target facility, and is a system with the production management function that performs real time monitoring & control, inspection, and adjustment of the target facility. Production management system according to an embodiment of the present invention is largely composed of CS, DBS, OS, facility management server. CS (Communication Server) is the center of communication and network management in the production management system, and sends and receives related information related to the operation and operation of the entire target facility in real time, and manages the communication status.

DBS is the center of data management in the production management system. It collects and manages all operation and operation related information generated in the target facility in real time, and provides the stored information along with basic information used for various analysis in real time or upon request of the operator. It plays a role.

The OS is the center of the human machine interface in the production management system. It monitors the operation status of all target facilities in real time and analyzes the operation status through the stored real time data and historical data.

The facility management server acquires various data necessary for facility management and operation information management in connection with CS and DBS, and analyzes and analyzes them according to real-time or operator requests through the OS.

(A) Control station

In the production management system, it is a flexible system that can be applied to various types of sites, and it is easy to expand and expand by providing not only a redundant configuration but also various communication functions. . In addition, it is equipped with an interface module of serial communication for communication with various measuring instruments, UPS, and digital switchboard.

(B) HMI solution

The HMI solution applied to the production management system is capable of real time monitoring and control, inspection and adjustment of target facilities in a wide range of regions, and is an open system manufactured according to international standards for flexible integration with various facilities. Architecture) is a structure that can be accommodated without changing the model even for new H / W and S / W release. In addition, HMI is equipped with a function to monitor and control all tag points of the target facility outside the operating room for integrated monitoring control and smooth operation. Can provide.

(C) Communication solution for Communication Server

Communication Server is the center of communication and network management of production management system. It is a facility that sends and receives related information according to operation and operation of target facility in real time and manages communication status. There should be no data loss. To this end, various programs necessary for smooth network communication between systems are required, and this communication management solution provides communication interface function for integration of various models, data synchronization function between monitoring and control systems, flexible scalability, and data loss even when communication is lost. Data Logger function, data backup and recovery function, etc. are provided.

(D) Facility management solutions

It is a solution to efficiently manage various target facilities distributed in a wide area. Facility management solutions require functions to minimize damage due to aging and failure of facilities through facility management and diagnosis of each treatment facility. Facility management solution is the management system such as installation related data, maintenance and alarm history, major components, consumables and spare parts for each facility, which is the main element of facility management system. Real-time information such as failure time is collected and the status diagnosis for each facility is performed on the basis of the collected information to prevent the problems that may occur due to aging. Facility management solutions should also enable the use of the system by remotely registered operators, including the management of consumables and spare parts.

(E) Main facilities for automatic operation

As mentioned above, the embodiment of the present invention is composed of the electrodialysis process unit 10, the electrolytic extraction process unit 20, the NF filtration process unit 70, the electro-oxidation process unit 80. At the front end of the electrodialysis process unit 10, which is a core process, the electrical conductivity and pH of the influent are measured, and the electrical conductivity of the treated water, the concentrated water and the electrode solution is measured in real time and used to determine the operating voltage and the operating time. The electrolytic extraction process unit 20, the NF filtration process unit 70, and the electro-oxidation process unit 80 are used to determine the operating time in the reaction tank by measuring the electrical conductivity and pH in the reaction tank. In particular, the NF filtration process unit 70 is provided with a pressure gauge 73, it is possible to determine the cleaning time of the membrane by determining the membrane contamination. In addition, for facility management, heavy metal recovery and inventory management, budget management, and notification of abnormalities are provided.

The production management system according to the embodiment of the present invention stores data acquired remotely from a reactor or data input by a user in a DB, and standardizes data using a data display function based on the data.

13 is a block diagram of a production management system program according to an embodiment of the present invention. As shown in Fig. 13 ①, data is structured to collect DB fields selected by a user, and then a formula is formed between the fields. Using the data display function, the user can create a new type of variable (DB field), which is created in the Variable Factory (②), and the created Variable (DB field) can be created through HMI Designer (Dashboard Designer, ③). The user can design the screen directly, and the screen created by the user through HMI Designer (Dashboard Designer) is finally expressed through ④. The production management system has the following functions.

(1) Data Standardization & Variable Expression: Function to generate and express heterogeneous data

(2) Dashboard Designer: A function that displays data on the screen by using the tool provided by the user.

(3) Report Designer: Creates and prints a document by using a tool that provides a report in the form desired by the user.

1) Data Standardization & Variable Expression

The production management system according to the embodiment of the present invention collects heterogeneous data of various types, converts them, and expresses them. Due to the nature of the production management system, there are many heterogeneous data of different characteristics, and data standardization technology is applied to allow the user to directly convert the acquired data into other forms. Data standardization is expressed as new meaning data after a separate calculation process based on a field type predefined in a database (hereinafter referred to as DB). This is a variable expression. Expression) technology allows the user to combine multiple fields and input predefined arithmetic rules. 14 is a block diagram of a data normalization method according to an embodiment of the present invention.

As shown in FIG. 14, when the previously acquired data is stored in a DB and a formula is input to the stored DB fields using the Variable Expression Editor, a new type field can be generated, and the user can create a new data field. The data can be analyzed and managed by creating the data, and the formula data of the newly created data field can be stored and managed separately.

2) Dashboard Designer

In the production management system according to an embodiment of the present invention, in addition to the aforementioned Data Standardization technology, the Dashboard Designer technology is applied to represent data of a desired form in the development stage. Dashboard Designer is a technology that allows users to easily display digitized data directly on a screen page, and can efficiently represent heterogeneous data in various forms. In addition, separate filtering (Filter, Master DB, Data Merge, etc.) can be set, which makes the data representation flexible.

3) Report Designer

Report Designer is a data report function of the production management system that can be used to report and print data in the form desired by the user. The Report function is built so that documents can be simply completed and printed immediately using the tools provided by Report Designer.

4) Watch dog

In the case of the existing communication, if a communication error is detected on the PLC side and is abnormal, the unilateral disconnection of the PLC may cause control confusion in the production management system, thereby reducing the stability of the system. Accordingly, the method is applied to improve the stability of the system by detecting each communication error. 15 is a block diagram of a watch dog according to an embodiment of the present invention.

In the production management system, if you see the number of 1 in the PLC, the PLC adds +1 and makes 2 to return to the production management system. Due to this, each system can grasp the communication status and abnormal status between each other, greatly improving the convenience of the operator. In addition, the watchdog function is inserted in each control loop to enable individual automatic operation for each control loop, so that the system is developed so that only the loop in which the problem occurs is converted to automatic operation by the PLC until the action is completed. Is configured to

In addition, the above-described apparatus and method may not be limitedly applied to the configuration and method of the above-described embodiments, but the embodiments may be selectively combined in whole or in part in each of the embodiments so that various modifications may be made. It may be configured.

1: Selective ion separation system to remove heavy metals in wastewater
2: influent electrical conductivity measurement unit
3: influent pH measurement unit
10: electrodialysis process
11: Treatment tank
12: Treatment tank electric conductivity measuring unit
13: concentrated water tank
14: Concentration tank electrical conductivity measuring unit
15: electrode bath
16: Electrode solution conductivity measurement unit
20: electrolytic extraction process
21: electrolytic extraction process electrical conductivity measurement unit
22: electrolytic extraction process pH measurement unit
30: # 1 Electrolytic Extraction Process
31: # 1 Electrolytic Extraction Process Electrical Conductivity Measurement Unit
32: # 1 electrolytic extraction process pH measurement unit
40: # 2 electrolytic extraction process
41: # 2 Electrolytic Extraction Process Part Conductivity Measurement Part
42: # 2 electrolytic extraction process pH measurement unit
50: #nelectrolytic extraction process
51: #nElectroconductivity Extraction Process Electrical Conductivity Measurement Unit
52: #nElectrolysis Extraction Process pH Measuring Unit
61: treated water conductivity measurement unit
62: treated water pH measurement unit
70: NF filtration process part
71: Filtration process electrical conductivity measurement unit
72: filtration process pH measurement unit
73: pressure gauge
80: electrooxidation process
81: electrical conductivity measuring unit electrical conductivity measuring unit
82: pH measurement part of the electrooxidation process part

Claims (18)

In a selective ion separation system for removing heavy metals in wastewater,
An electrodialysis process unit for introducing wastewater into the wastewater by electrodialysis to separate the discharged wastewater into concentrated water and treated water including cyanide;
The concentrated water is introduced, the electrolytic extraction process unit for recovering heavy metals through electrolytic extraction;
An NF filtration process unit for discharging the treated water discharged from the electrodialysis process unit and the treated water discharged from the electrolytic extraction process unit to remove the treated water and the concentrated water concentrated heavy metals through NF membrane filtration; And
The treatment water of the NF filtration process unit flows in, the electro-oxidation process unit is an electrooxidation process unit for oxidizing and removing the cyan compound and organic matter present in the treated water of the NF filtration process unit; Selective ion separation system.
The method of claim 1,
Selective ion separation system for removing heavy metals in the waste water, characterized in that it further comprises a suspended solids removal process unit provided in the front end of the electrodialysis process unit to remove the suspended substances.
The method of claim 2,
The electrodialysis process unit includes a treatment tank, a concentration tank, and an electrode solution tank, and the concentration of heavy metals increases as the operation time passes in the electrode solution used in the electrodialysis process unit, and thus, electrolyzed together with the concentrated water after a certain time. Selective ion separation system for removing heavy metals in the waste water, characterized in that the transfer to the extraction process.
The method of claim 3, wherein
The electrolytic extraction process is composed of a plurality of stages connected in series according to the type of heavy metal, in order to recover the heavy metal containing the concentrated water and heavy metal in the electrode solution, depending on the type of heavy metal to be recovered depending on the pH and applied voltage Selective ion separation system for removing heavy metals in the wastewater, characterized in that to recover the heavy metals through the adjustment of.
The method of claim 4, wherein
The NF filtration process part is treated water of the electrodialysis process unit and the treated water of the electrolytic extraction process unit flows in, the treated water removing the heavy metal as a cation is transferred to the electrooxidation process unit, the concentrated water concentrated heavy metal is electrodialysis process unit Selective ion separation system for removing heavy metals in the waste water, characterized in that mixed with the waste water of the inlet of the front end is reintroduced to the electrodialysis process.
The method of claim 5,
The electrooxidation process unit oxidizes and removes cyanide compounds and organics present in the treated water of the NF filtration process unit, hypochlorous acid produced in the electrooxidation process unit is used to clean the NF filtration membrane of the NF filtration process unit. Selective ion separation system for removing heavy metals in wastewater.
The method of claim 5,
An influent electric conductivity measuring unit for measuring the electrical conductivity of the wastewater flowing into the electrodialysis process unit, an influent pH measuring unit for measuring the pH of the wastewater, and a treatment tank electric conductivity measuring unit for measuring the electrical conductivity in the treatment tank; Selective ion separation system for removing heavy metals in the wastewater, characterized in that the electrical conductivity measuring unit for measuring the electrical conductivity in the concentration tank, and the electrode liquid conductivity measuring unit for measuring the electrical conductivity in the electrode solution tank .
The method of claim 7, wherein
The electrical conductivity change rate is based on the measured values of the inflow water conductivity measuring unit, the inflow water pH measuring unit, the treated tank electric conductivity measuring unit, the concentrated tank electric conductivity measuring unit, and the electrode solution bath electrical conductivity measuring unit. Selective ion separation system for removing heavy metals in the wastewater, characterized in that for calculating and adjusting the operating voltage of the electrodialysis process unit based on the electrical conductivity change rate.
The method of claim 8,
The heavy metal in the wastewater, characterized in that it further comprises an electrolytic extraction process pH measuring unit for measuring the pH in the reaction tank of the electrolytic extraction process unit, and an electrolytic extraction process unit electrical conductivity measuring unit for measuring the electrical conductivity in the reaction tank of the electrolytic extraction process unit. Selective ion separation system to remove the.
The method of claim 9,
The electrical conductivity change rate is calculated based on the measured value of the electrical conductivity measurement unit of the electrolytic extraction process, and the operating time in the reaction tank is determined using the electrical conductivity change rate.When the concentrated water is introduced, the pH is measured by the pH measuring unit of the electrolytic extraction process. Selective ion separation system for removing heavy metals in the waste water, characterized in that to recover the heavy metals by adjusting to an appropriate pH range and applying electricity.
The method of claim 10,
NF filtration process unit pH measurement unit for measuring the pH in the reaction tank of the NF filtration process unit, NF filtration process unit electrical conductivity measurement unit for measuring the electrical conductivity in the reaction tank of the NF filtration process unit, and a pressure gauge for measuring the pressure in the reaction tank Selective ion separation system for removing heavy metals in the wastewater, characterized in that it further comprises.
The method of claim 11,
The electrical conductivity change rate is calculated based on the measured value of the electrical conductivity measurement unit of the NF filtration process unit, and the operating time in the reaction tank is determined using the electrical conductivity change rate, and the pH is measured through the pH measurement unit of the NF filtration process unit to obtain a proper pH range. Selective ion separation system to remove heavy metals in the wastewater, characterized in that the adjustment.
The method of claim 12,
The heavy metal in the wastewater, characterized in that it further comprises an electrooxidation process pH measurement unit for measuring the pH in the reaction tank of the electrooxidation process unit, and an electrical conductivity measurement unit for measuring the electrical conductivity in the reaction tank of the electrooxidation process unit. Selective ion separation system to remove the.
The method of claim 13,
The electrical conductivity change rate is calculated based on the measured value of the electrical conductivity measuring unit of the electrooxidation process, the operating time in the reaction vessel is determined using the change in electrical conductivity, and the pH is measured by measuring the pH when the treated water flows into the electrooxidation process unit. Selective ion separation system for removing heavy metals in the waste water, characterized in that the cyan and the organic material is removed by adjusting the power supply.
In the control method of the electrodialysis process of the selective ion separation system for removing heavy metals in the waste water according to claim 8,
Measuring whether the pH of the wastewater measured by the influent pH measuring unit is within a predetermined range, and adjusting the pH so that the pH is within a proper range;
If the rate of change of conductivity in the treatment tank is within the setting range, checking whether the rate of change of conductivity in the concentration bath is within the setting range and checking whether the rate of change of conductivity in the electrode solution tank is within the setting range;
If the rate of change of the electrode liquid electrical conductivity of the treatment tank, the concentration tank, and the electrode solution tank is within the setting range, driving the voltage by increasing the applied voltage; And
A change rate of the conductivity decreases as time passes, and if the electric conductivity change rate decreases within a predetermined range, maintaining or decreasing the applied voltage and finally stopping the operation when the operating voltage reaches the initial applied voltage. Control method of selective ion separation system for removing heavy metals in the wastewater.
In the control method of the electrolytic extraction process of the selective ion separation system for removing heavy metals in the waste water according to claim 10,
A first step of checking pH when the rate of change of electrical conductivity is within a set range;
A second step of continuing the operation if the value of the pH is within an appropriate range and operating after adjusting the pH if the pH is exceeded;
a third step of stopping the operation if the pH is within an appropriate range and moving the treated water to a subsequent electrolytic extraction process; And
And performing the first to third steps with respect to all the electrolytic extraction processes. The control method of the selective ion separation system for removing heavy metals in the wastewater.
In the control method of the NF filtration process of the selective ion separation system for removing heavy metals in the waste water according to claim 12,
If the rate of change of electrical conductivity is within a setting range, checking pH;
Continuing operation when the value of the pH is within an appropriate range, and operating after adjusting the pH when exceeding the range; And
Stopping the operation if the pH is within an appropriate range and moving the treated water to a subsequent electrooxidation process; control method of the selective ion separation system for removing heavy metals in the waste water.
A control method of an electrooxidation process of a selective ion separation system for removing heavy metals in wastewater according to claim 14,
If the rate of change of electrical conductivity is within a setting range, checking pH;
Continuing operation when the value of the pH is within an appropriate range, and operating after adjusting the pH when exceeding the range; And
Stopping the operation if the pH is within an appropriate range and moving the treated water to a treated water tank or a reuse process; control method of a selective ion separation system for removing heavy metals in waste water.

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